Hitsu's only chance would be releasing bankai immediately, depending on distance he could still lose.
If Hitsu tries to engage in swordplay, well let's just say Zoro won't be as patient as Harribel.
Hitsugaya freezes Zoro ftw.
Well, Toshiro can fly and spam kido and zanpakuto attacks so there's that.
Hyōten Hyakkasōor death.
Zoro wins with mid difficulty at best. Hitsuguya has yet to show he's proficient in Kido. So no, he won't be spamming Kido. His only hope would be to use the attack he used on Harribel
Hitsugaya will need to go Bankai first thing first in oeder not to die.
Hyoten Hyakkaso will give Hitsu the win if he's bloodlusted.
It covers a radius of 12 kilometers, and this is the size of a large city!
If he maintains his distance, he can take this quite easily.
I actually misread the OP. Pre-Skip Zoro does indeed lose. I was thinking of current Zoro.
If he stays in the air beyond Zoro's reach and uses that technique then Zoro is essentially helpless. Any other scenario though and I'd give Zoro the majority.
Zoro could always throw his sword while Toshiro is about to do that.
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